This invention relates to a performance management of a computer system which includes a storage system.
There has been realized a storage network in which a plurality of computers access an integrated storage system via a communication network. Such a storage network can increase utilization efficiency of the storage system enlarged more and more and reduce management costs, and has therefore started to be widely used as an architecture for a data center. A computer system to which the storage network has been introduced executes applications critical in business in many cases, and therefore requires high processing performance, availability, and fault-tolerance. To meat such requirements, the storage system performs various types of processing.
For example, in the computer system to which the storage network has been introduced, concentration of loads on a specific storage resource such as a port or a processor may cause a drop in performance of access to a logical volume. To deal with such a case, a technology has been proposed in which the loads of the storage resource are dispersed by moving the logical volume dropped in performance (e.g., refer to JP 2001-337790 A). The movement of the logical volume is called a volume migration (simply referred to as migration hereinafter). The storage system executes a migration, whereby the drop in performance of the applications critical in business can be prevented.
The migration may be executed for purposes other than the load dispersion. For example, when importance of stored data is reduced with a passage of time, it is possible to reduce costs of storing the data by migrating the data to an inexpensive storage system.
Another example of processing executed by the storage system is so-called remote copying. Data stored in the storage system may be lost due to system faults, disasters, artificial mistakes, or the like. To deal with such a case, a so-called remote copy technology has been proposed in which data is made redundant by transferring a copy of the data stored in the storage system to another storage system to store it (e.g., JP 2003-122509 A). Since the storage system executes remote copying to make the data redundant, even when data is lost from one storage system, the other storage system can take over the processing. As a result, it is possible to improve availability and fault-tolerance of the computer system.